Lubricant and fuel compositions containing reaction products of polyalkenyl succinimides, aldehydes, and triazoles

ABSTRACT

Disclosed is an additive for liquid hydrocarbon fuel composition, particularly diesel fuels. The additive composition is the reaction product of polyalkenyl-substituted succinimides, aldehydes, and triazoles. It also finds use in lubricant compositions.

This is a divisional of copending application Ser. No. 290,405, filed onDec. 29, 1988 and now U.S. Pat. No. 4,897,086.

NATURE OF THE INVENTION

This invention relates to lubricant compositions. More specifically itis concerned with the reaction products of polyalkenyl-substitutedsuccinimides, aldehydes, and triazoles useful as multifunctionaldetergents, dispersants, and antioxidants in lubricant compositions.

BACKGROUND OF THE INVENTION

Impurities occurring in diesel fuels can produce soluble and insolublematerials which are responsible for gum deposits and discoloration ofthe fuel. Other impurities may result from handling, corrosion ofstorage vessels and may even be introduced by the refiner to prevent orsolve other problems with the fuel such as oxidation, rust promotion,etc. The end result can be the formation of deposits in the dieselengine, particularly with respect to the fuel injectors. The eventualresult is poor engine performance with increased noise, startingproblems and decreased power output and fuel economy. A primary purposeof this invention accordingly is to provide an additive for fuels,particularly diesel fuels, which will help reduce engine deposits.Another purpose of this invention is to provide an additive which willimprove the stability and cleanliness of lube oil compositions.

SUMMARY OF THE INVENTION

Briefly stated this invention comprises in one aspect a lubricantcomposition and in another aspect a liquid hydrocarbon fuel compositioncontaining in addition to a major portion of a lubricant or hydrocarbonfuel a minor portion of an additive composition which is the reactionproduct of a polyalkenyl-substituted succinimide, an aldehyde, and atriazole. The invention further comprises the method for making theadditive composition. The additive itself is a multifunctional additivein that, in addition to its detergent/dispersant activity, it operatesas an anti-rust, anti-wear, and friction reducing agent.

DESCRIPTION OF THE INVENTION

As indicated above the this invention comprises the lubricantcomposition or the liquid hydrocarbon fuel composition containing thereaction product of a polyalkenyl-substituted succinimide, an aldehyde,and a triazole. The substituted or modified succinimides have thestructural formula: ##STR1## where R is an alkyl or alkenyl group of 9to 150 carbon atoms, and X is 1 to 4. Although polyisobutylene is aparticularly preferred substituent, other substituents can be, but arenot limited to, polypropylene, other polyolefins, as well as monomericolefins.

The triazoles have the structural formula: ##STR2## where R¹ is hydrogenor an alkyl, aryl, arylalkyl, or alkylaryl group of 1 to 12 carbonatoms. A preferred triazole is tolyltriazole. The aldehyde used inpreparing the reaction product can be alkyl, aryl, alkylaryl, orarylalkyl containing 1 to 12 carbon atoms. Also included isformaldehyde, the paraformaldehyde form being more preferred.

The polyalkenyl-substituted succinimide, aldehyde, and triazole arereacted in a mole ratio of succinimide to aldehyde to triazolerespectively of between 1 to 0.1 to 0.1 and 1 to 4 to 4, preferably at atemperature of 100° C. to 200° C. at ambient pressure. If desired thereaction can be conducted in a carrier solvent such as xylene or tolueneand in a non-reactive atmosphere. After reaction is complete thereaction mass is treated to remove any solvent or water of reaction. Theresulting product is the desired additive product. Although we do notwish to be bound by it, it is thought that the reaction product may havethe general formula: ##STR3## where R is an alkyl or alkenyl group of 9to 150 carbon atoms, , R¹ and R² are each hydrogen or an alkyl, aryl,arylalkyl, alkylarlyl group of 1 to 12 carbon atoms, y is greater than0, and x+y is equal to 1 to 4.

In preparing a fuel composition the additive is added at a rate ofbetween 25 and 500 pounds of additive per 1000 barrels of fuel. Theliquid fuel can be a liquid hydrocarbon fuel or an oxygenated fuel ormixtures thereof. Liquid hydrocarbon fuels include gasoline, fuel oils,diesel oils, and alcohol fuels including methyl and ethyl alcohols andethers.

It is to be understood that the liquid fuel compositions describedherein can also contain other materials. For example, corrosioninhibitors, co-antioxidants, and the like can be used.

In preparing a lubricant composition the additive is added to the baselubricating oil stock in a concentration of between 0.1 and 10 percentby weight of the total composition. In general, the mineral oils, bothparaffinic, naphthenic and mixtures thereof, employed as a lubricatingoil or as the grease vehicle, can be of any suitable lubricatingviscosity range, as for example, from about 45 SSU at 100° F. to about6000 SSU at 100° F., and preferably from about 50 to about 250 SSU at210° F. These oils may have viscosity indexes ranging to 100 or higher.Viscosity indexes from about 70 to about 95 are preferred. The averagemolecular weights of these oils can range from about 250 to about 800.

Where the lubricant is employed as a grease, the lubricating oil isgenerally used in an amount sufficient to balance the total greasecomposition, after accounting for the desired quantity of the thickeningagent, and other additive components included in the grease formulation.A wide variety of materials can be employed as thickening or gellingagents. These can include any of the conventional metal salts or soaps,such as calcium, or lithium stearates or hydroxystearates, which aredispersed in the lubricating vehicle in grease-forming quantities in anamount to impart to the resulting grease composition the desiredconsistency. Other thickening agents that can be employed in the greaseformulation comprise the non-soap thickeners, such as surface-modifiedclays and silicas, aryl ureas, calcium complexes and similar materials.In general, grease thickeners can be employed which do not melt anddissolve when used at the required temperature within a particularenvironment; however, in all other respects, any material which isnormally employed for thickening or gelling hydrocarbon fluids forforming grease can be used in preparing the aforementioned improvedgrease in accordance with the present invention.

In instances where synthetic oils, or synthetic oils employed as thevehicle for the grease, are desired in preference to mineral oils, or inpreference to mixtures of mineral and synthetic oils, various syntheticoils may be utilized successfully. Typical synthetic oil vehiclesinclude polyisobutylenes, polybutenes, hydrogenated polydecenes,polypropylene glycol, polyethylene glycol, trimethylol propane esters,neopentyl and pentaerythritol esters, di(2-ethylhexyl) sebacate,di(2-ethylhexyl) adipate, dibutyl phthalate, fluorocarbons, silicateesters, silanes, esters of phosphorus-containing acids, liquid ureas,ferrocene derivatives, hydrogenated synthetic oils, chain-typepolyphenyls, siloxanes and silicones (polysiloxanes) andalkyl-substituted diphenyl ethers typified by a butyl-substitutedbis(p-phenoxy phenyl) ether, and phenoxy phenylethers.

It is to be understood that the grease compositions described herein canalso contain other materials, eg, corrosion inhibitors, extreme pressureagents, viscosity index improvers, antioxidants, antiwear agents and thelike can be used. These include, but are not limited to, phenates,sulfonates, succinimides, zinc dialkyl or diaryl dithiophosphates, andthe like.

EXAMPLE 1

A weight of 10.7 grams (0.08 mole) of tolyltriazole, 236.2 grams (0.08mole) of a polyisobutenyl succinimide (made from tetraethylene pentamineand a polyisobutenyl succinic anhydride which is the reaction product ofmaleic anhydride and a 920 MW polyisobutylene), and 200 of toluene werecharged to a 500 ml reactor equipped with an N₂ inlet, mechanicalstirrer, thermometer, and Dean Stark trap. The temperature was raised to70° C. and 1.3 grams (0.04 mole) paraformaldehyde was added. After ahalf hour at this temperature another 1.3 grams portion ofparaformaldehyde was added. The reaction was brought to reflux. After1.5 hours, 1.6 ml of water had been collected. The reaction temperaturewas increased to 150° C. by removing solvent through the Dean Starktrap. It was kept at this temperature for one hour during which timeresidual solvent was removed under a stream of N₂. The viscous productwas filtered through a bed of hot celite.

EXAMPLE 2

A weight of 8.0 grams (0.06 mole) of tolyltriazole, 87.7 grams (0.03mole) of a polyisobutenyl succinimide (made from tetraethylene pentamineand a polyisobutenyl succinic anhydride which is the reaction product ofmaleic anhydride and a 920 MW polyisobutylene), and 100 ml of toluenewere charged to a 500 ml reactor equipped with an N₂ inlet, mechanicalstirrer, thermometer, and Dean Stark trap. The temperature was raised to70° C. and 1.9 grams (0.06 mole) paraformaldehyde was added. Thereaction was brought to reflux. After 4.0 hours, 1.1 ml of water hadbeen collected. The solvent was removed via rotary evaporation, firstunder house vaccuum (250-300 mm Hg) and then with a vacuum pump (1-3mmHg). The viscous product was filtered through a bed of hot celite.

EXAMPLE 3

The procedure from Example 2 was followed with the following exception:The ratio of tolyltriazole to succinimide to paraformaldehyde waschanged to 3 to 1 to 3.

EXAMPLE 4

The procedure from Example 2 was followed with the following exceptions:The ratio of tolyltriazole to succinimide to paraformaldehyde waschanged to 1 to 1 to 1 and the polyisobutenyl succinimide was made froma 460 MW polyisobutylene.

EXAMPLE 5

The procedure from Example 4 was followed with the following exception:The ratio of tolyltriazole to succinimide to paraformaldehyde waschanged to 0.1 to 1 to 0.1.

FUEL TEST

The product obtained in Example 4 above was blended into diesel fuel ina ratio of 50 lb/1000 barrels and the fuel was tested for color andoxidative stability using a 90 minute stability test conducted at 300°F. Fuel (ASTM D 1500) color was determined using a colorimeter. Sedimentformation was determined by vacuum filtration of the fuel through twoWhatman #1, 4.25 cm filters. Then, the appearance of the top filter israted by comparing it to the standard set of filter pads, numbered 1 to20, where a rating of 20 indicates poor stability (more sedimentformation). Test results are as follows.

    ______________________________________                                                         Color       Filter Rating                                    Fuel             Initial Aged    Initial                                                                             Aged                                   ______________________________________                                        Base Diesel Fuel 4.5     7.0     5     16                                     Base + 100 lb of Commercial                                                                    4.5     5.5     5     2                                      Detergent Additive Package                                                    Containing an Anti-Rust                                                       Additive per 1000 Barrels of                                                  Diesel Fuel                                                                   Base + 50 lb of additive of                                                                    4.5     5.0     5     2                                      Example 4 per 1000 Barrels of                                                 Diesel Fuel                                                                   ______________________________________                                    

The product of this invention was also tested for its ability to keepfuel injectors clean in a Peugeot 505 STD equipped with standard pintleinjectors. To accelerate injector coking, the vehicle was operated for 6hours under severe steady-state conditions of high speed and load. Theextent of injector deposits was assessed based on the air flowcharacteristics of the nozzle before and after tests. Performancecomparisons are based on percent air flow restriction versus newinjectors at 0.1 mm needle lift.

    ______________________________________                                        Fuel                 % Restriction                                            ______________________________________                                        Base                 51                                                       Base + 100 lb/MB Commercial                                                                        23                                                       Detergent Additive Package                                                    Base + 50 lb/MB Examp1e 4                                                                           5                                                       ______________________________________                                    

From these results it is readily apparent that the product of thisinvention not only imparts color stability and reduces sedimentformation but that it is effective in keeping fuel injectors clean.

EXAMPLE 6

The procedure from Example 2 was followed with the following exceptions:Benzaldehyde was substituted for paraformaldehyde and the ratio oftolyltriazole to succinimide to benzaldehyde was changed to 1 to 1 to 1.

EXAMPLE 7

The procedure from Example 2 was followed with the folowing exceptions:2-ethylhexanal was substituted for paraformaldehyde and the ratio oftolyltrizole to succinimide to 2-ethylhexanal was changed to 1 to 1 to1.

EXAMPLE 8

The procedure from Example 2 was followed with the following exceptions:Salicylaldehyde was substituted for paraformaldehyde and the ratio oftolyltriazole to succinimide to salicylaldehyde was changed to 1 to 1 to1.

EXAMPLE 9

The procedure from Example 6 was followed with the following exceptions:The ratio of tolyltrizole to succinimide to benzaldehyde was changed to2 to 1 to 2.

EXAMPLE 10

The procedure from Example 7 was followed with the following exceptions:The ratio of tolyltriazole to succinimide to 2-ethylhexanal was changedto 2 to 1 to 2.

EXAMPLE 11

The procedure from Example 8 was followed with the following exceptions:The ratio of tolyltrizole to succinimide to salicylaldehyde was changedto 2 to 1 to 2.

The additive described above were evaluated to show their antioxidantcapabilities in a concentration of 4 percent in a fully formulatedmarine diesel lubricant. Results were as follows.

    ______________________________________                                        B-10 Catalytic Oxidation Test, 375° F., 24 Hours                       Additive          NN     % NN                                                 ______________________________________                                        None              4.1    72.9                                                 Commercial        5.2    77.1                                                 Dispersant                                                                    Example 2         5.2    47.8                                                 Example 5         5.1    62.4                                                 Example 6         3.7    38.1                                                 Example 7         4.7    45.3                                                 Example 8         4.1    34.7                                                 Example 9         4.9    56.3                                                 Example 10        4.4    47.7                                                 ______________________________________                                    

What is claimed is:
 1. An improved lubricant composition comprising a major proportion of an oil of lubricating viscosity or a grease prepared thereof and between about 0.1% and 10% by weight of the total composition of a multifunctional detergent/dispersant/antioxidant reaction product obtained by reacting a polyalkenyl-substituted succinimide having the structural formula: ##STR4## where R is an alkyl or alkenyl or alkenyl group of 9 to 150 carbon atoms with a triazole having the structural formula: ##STR5## where R¹ is hydrogen or an alkyl, aryl, arylalkyl, or alkylaryl group of 1 to 12 carbon atoms with an aldehyde wherein the polyalkenyl-substituted succinimide, aldehyde and triazole are reacted in a mole ratio of succinimide to aldehyde to triazole respectively of between about 1 to 0.1 to 0.1 and about 1 to 4 to 4 at temperatures varying from about 100° C. to about 200° C. at ambient pressures.
 2. The composition of claim 1 wherein the polyalkenyl-substituted succinimide is a polyisobutenyl succinimide.
 3. The composition of claim 1 wherein the triazole is tolyltriazole.
 4. The composition of claim 1 wherein the reaction product has the structural formula: ##STR6## where R is an alkyl or alkenyl group of 9 to 150 carbon atoms,, R¹ and R² are each hydrogen or an alkyl, aryl, arylalkyl, alkylarlyl group of 1 to 12 carbon atoms, y is greater than 0, and x+y is equal to 1 to
 4. 5. The composition of claim 1 wherein the reaction is conducted in a carrier solvent selected from the group consisting of xylene and toluene.
 6. A method for making a lubricant composition comprising adding to a lubricant between about 0.1% and about 10% by weight of the total composition of the reaction product described in claim
 1. 7. The composition of claim 1 wherein the aldehyde is selected from the group consisting of formaldehyde, paraformaldehyde, benzaldehyde, salicylaldehyde, and 2-ethylhexanal.
 8. The composition of claim 7 wherein the aldehyde is formaldehyde.
 9. The composition of claim 1 wherein the oil of lubricating viscosity is selected from (1) mineral oils, (2) synthetic oils or (3) a mixture of (1) and (2) or (4) a grease prepared from any one of (1), (2) or (3).
 10. The composition of claim 9 wherein the oil of lubricating viscosity is (1) a mineral oil.
 11. The composition of claim 9 wherein the oil of lubricating viscosity is (2) a synthetic oil.
 12. The composition of claim 9 wherein the oil of lubricating viscosity is (3) a mixture of (1) and (2).
 13. The composition of claim 9 comprising a grease. 